If you've ever seen an actual Shakespeare play, it's much easier to understand.
Actually, as someone who's seen nearly every Shakespeare play live or in movie form (inc. one at the Globe) and studied him for over a decade, I find him easier to read for understanding than to watch. The one exception to that "rule" is Much Ado About Nothing
, with Branagh's version. Then again, I read Middle English nearly fluently, so Elizabethan English is easy to read and I rarely use the language footnotes.
You also get to see just how raunchy Shakespeare was
Picked up all of this from "merely" reading him. Most of his humor comes from innuendo and bodily functions (same with Chaucer, actually).
there are the transvestite plays
Basically every Shakespeare play and virtually all British comedy? And ancient Greek comedy? Transvestitism is one of the mainstays of dramatic comedy in nearly every culture throughout history.
I think Shakespeare's plays are fine for HS audiences, even younger (heck they were fine for children when he wrote them), however most American high schools tend to only teach the tragedies and histories. They generally tend to ignore the comedies, which is a definitely problem.